盐酸克林霉素对猪链球菌病的疗效试验

从辽宁省3个地区分离到27株猪链球菌病的病原,对其进行了分离和鉴定,致病菌是C群马链球菌.用平皿二倍稀释法测定了克林霉素等12种药物对临床分离的27株链球菌的MIC,结果表明,27株链球菌对克林霉素敏感,MIC50为0.125μg/mL.临床疗效试验表明,克林霉素组的死亡率、有效率、治愈率与感染组比较差异极显著(P＜0.01),表明克林霉素对猪链球菌病有很好的疗效.     

奶牛急性乳腺炎病原菌的耐药性分析

对奶牛乳腺炎病原菌进行了分离和鉴定,鉴定出致病菌是金黄色葡萄球菌和B群链球菌.用平皿二倍稀释法,测定了克林霉素等12种药物对临床分离的金黄色葡萄球菌和B群链球菌的MIC,盐酸克林霉素对金黄色葡萄球菌MIC50最低为0.06 μg/ml,对B群链球菌的MIC50最低为0.125 μg/ml.克林霉素对金黄色葡萄球菌和B群链球菌不产生耐药性.     

江苏部分奶牛场乳腺炎病原菌的分离鉴定、耐药性及血清型研究

为查明江苏部分奶牛场乳腺炎病原菌区系分布、主要病原菌药物敏感性及其血清型,本研究从5个奶牛场采集105份临床型和144份隐性乳腺炎奶样进行了细菌分离鉴定,并对分离鉴定出的6种主要病原菌进行了药敏试验,同时对分离鉴定出的12株金黄色葡萄球菌和17株无乳链球菌,采用多重PCR进行了基因分型,并对金黄色葡萄球菌进行了血清学分型。细菌分离鉴定结果显示,5个奶牛场临床型和隐性乳腺炎病原菌检出率分别为74.34%和61.81%。病原菌区系分布主要为大肠杆菌89株(24.25%)、粪肠球菌64株(17.44%)、克雷伯氏菌23株(6.27%)、志贺氏菌19株(5.18%)、无乳链球菌17株(4.63%)、屎球菌14株(3.81%)、金黄色葡萄球菌12株(3.27%)、停乳链球菌1株(0.27%)、乳房链球菌1株(0.27%)和绿脓杆菌1株(0.27%)。药物敏感性试验结果显示,6种主要病原菌均对克林霉素耐药,耐药率达50.00%~93.75%,均对氨苄西林和氯霉素敏感,敏感率为75.00%~100%。主要病原菌血清型分型结果显示,金黄色葡萄球菌有2个血清型,主要为荚膜多糖336型(66.67%)和5型(33.33%),无乳链球菌主要有2个血清型,主要为Ⅱ型(64.71%)和Ia型(35.29%)。本研究为该地区奶牛乳腺炎临床合理用药及综合防控提供了依据。     

奶牛乳腺炎病原菌的分离鉴定及中药透皮剂治疗

对佳木斯市8所规模型奶牛场做了乳腺炎发病情况调查,随机采集了88份临床型乳腺炎乳样和176份隐性乳腺炎乳样做了细菌学检查,并对分离得到的病原菌进行鉴定,同时采用中草药透皮剂治疗发病奶牛.试验结果表明,引起奶牛乳腺炎主要病原菌包括金黄色葡萄球菌、表皮葡萄球菌、无乳链球菌、乳房链球菌、化脓链球菌、大肠杆菌、克雷伯氏菌、绿脓杆菌、沙门氏菌;中药透皮剂治疗奶牛乳腺炎实验表明治疗效果良好.     

奶牛临床型乳腺炎致病菌分离鉴定及2种常见用药方案的疗效研究

为了研究奶牛乳腺炎致病菌种类,同时比较青霉素、链霉素合并使用与沃瑞特单独使用在奶牛临床型乳腺炎的治疗中的疗效差异,以100头患有临床型乳腺炎的奶牛为研究对象,对从乳样中分离到的细菌进行鉴定;在同一饲养管理条件下将上述患牛分为对照组（4头）、沃瑞特组（50头）、青链霉素组（46头）进行疗效对比研究。结果表明,致病菌葡萄球菌的分离率为37.0%、大肠杆菌为30.1%、克雷伯菌为 18.3%、链球菌为2.4%,其他菌为12.2%,占比例最高的是葡萄球菌;2种用药方案均收到良好的治疗效果,青链霉素组治愈率为78.26%,沃瑞特治愈率为66.00%,青链霉素组治愈率显著高于沃瑞特组。     

朱砂七提取物体外抑菌和抗病毒活性部位筛选

为筛选朱砂七提取物体外抑制9株临床分离致病菌和抑制新城疫病毒(NDV)的活性部位,采用琼脂扩散和试管稀释法进行体外抑菌试验,MTT法和鸡胚法测定了朱砂七提取物对NDV在鸡胚成纤维细胞(CEF)和鸡胚内增殖的影响.结果显示,朱砂七乙酸乙酯部位(PCE)对9株临床分离菌的MBC均小于100 g/L;朱砂七氯仿部位(PCC)有一定的抑菌作用;大黄素对沙门菌(鸡)、链球菌(猪)、无乳链球菌(奶牛)、表皮葡萄球菌(奶牛)和金黄色葡萄球菌(奶牛)的MBC分别为5,2.5,2.5,2.5,1.25 g/L;PCE进一步分离部位PCEA对沙门菌(鸡)、链球菌(猪)、无乳链球菌(奶牛)、表皮葡萄球菌(奶牛)和金黄色葡萄球菌的MBC分别为24,24,12,6,6 g/L.PCC和大黄素对NDV在CEF上增殖的抑制作用不明显;PCE对NDV在CEF上的抑制率为39.12%(P＜0.01),PCEA对NDV在CEF上的抑制率为72.33%(P＜0.01);PCEA对NDV在鸡胚中增殖具有抑制作用,其预防组和药毒混合组与病毒对照组的血凝效价差异显著(P＜0.05),而治疗组与病毒对照组差异不显著.由此可知,朱砂七提取物具有抑制细菌作用,PCE和PCEA对NDV的增殖具有一定的抑制作用.     

长春市某奶牛场乳腺炎病原菌的分离鉴定及耐药性分析

奶牛乳腺炎是制约奶牛养殖效益和奶品质的主要疾病之一，为了解当前长春市某大型集约化奶牛场奶牛乳腺炎病原菌流行和耐药情况，本试验对该场奶牛乳腺炎发病情况进行了调查，对采集的119份临床型乳腺炎乳样进行细菌分离鉴定并对分离鉴定的病原菌进行小鼠致病性试验和药敏试验。结果显示：该场奶牛乳腺炎发病率在4%左右，初产牛乳腺炎发病率明显高于经产牛，乳腺炎发病率还与胎次、年龄等因素相关。本试验共分离鉴定出木糖葡萄球菌49株(42.2%)、松鼠葡萄球菌39株(33.6%)、大肠杆菌15株(12.9%)、金黄色葡萄球菌5株(4.3%)、无乳链球菌3株(2.6%)、菠萝泛菌3株(2.6%)、产酸克雷伯菌1株(0.9%)和铜绿假单胞菌1株(0.9%);其中菠萝泛菌、无乳链球菌和铜绿假单胞菌对小鼠具有较强致病性。药敏试验结果显示，分离菌株的耐药性普遍存在，大肠杆菌和铜绿假单胞菌耐药种类最多。除无乳链球菌外，其他菌株均对庆大霉素或阿米卡星敏感，可作为该场奶牛乳腺炎治疗首选药物。本试验通过对该场乳腺炎调查、分离菌鉴定和耐药性分析，为该场乳腺炎的防治提供了参考依据。     

包头地区临床型奶牛乳腺炎病原菌的分离与鉴定

临床型奶牛乳腺炎主要是由多种非特定病原微生物引发的奶牛乳房及乳汁表现出明显临床症状的一种乳腺疾病。从包头地区5个奶牛场33头奶牛的77份乳样中分离得到98株病原菌,主要病原经生化试验鉴定为金黄色葡萄球菌、表皮葡萄球菌、腐生葡萄球菌、无乳链球菌、乳房链球菌、乳链球菌、牛链球菌、粪链球菌、棒状杆菌属、酵母菌和大肠埃希菌、克雷伯菌属、变形杆菌属、志贺菌属、肠杆菌属、沙门菌属。研究结果可为包头地区临床型奶牛乳腺炎的防治工作提供参考。     

一例奶牛乳房炎病例病原菌分离及鉴定

对辽宁抚顺某奶牛养殖场中1例临床型乳房炎阳性病例进行病原菌分离及生化反应鉴定.结果表明,在2个患病乳区的乳样中共筛查到5株大肠杆菌、5株金黄色葡萄球菌、4株腐生葡萄球菌、2株表皮葡萄球菌、2株无乳链球菌、1株停乳链球菌及1株乳房炎链球菌.该结果可为该厂奶牛乳房炎合理治疗提供参考.     

沈阳地区奶牛乳房炎细菌分离鉴定与优势菌株药敏试验

为更好地制定奶牛乳房炎防治措施,本研究采集了沈阳地区6个奶牛场289头临床型乳房炎患牛的乳样进行细菌的分离鉴定,共分离得到4类9种细菌共计354株细菌,主要为大肠杆菌、金黄色葡萄球菌、无乳链球菌、乳房链球菌,并对高发的大肠杆菌菌株进行了19种常见抗生素的药敏试验,发现其对哌拉西林、氧氟沙星等高度敏感,对克林霉素、万古霉素等高度耐药。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.